s908az32ag2cfue Freescale Semiconductor, Inc, s908az32ag2cfue Datasheet - Page 102

• Manufacturer Part Number: s908az32ag2cfue
• Description: M68hc08 Microcontrollers 8-bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Clock Generator Module (CGM)
MUL7–MUL4 — Multiplier Select Bits
VRS7–VRS4 — VCO Range Select Bits
102
These read/write bits control the modulo feedback divider that selects the VCO frequency multiplier, N.
(See
configures the modulo feedback divider the same as a value of $1. Reset initializes these bits to $6 to
give a default multiply value of 6.
See
These read/write bits control the hardware center-of-range linear multiplier L, which controls the
hardware center-of-range frequency, f
8.5.1 PLL Control
register (PCTL) is set. See
select bits disables the PLL and clears the BCS bit in the PCTL. (See
and
give a default range multiply value of 6.
8.3.2.5 Special Programming Exceptions
Table
8.3.2.1 Circuits
8-3.
The multiplier select bits have built-in protection that prevents them from
being written when the PLL is on (PLLON = 1).
The VCO range select bits have built-in protection that prevents them from
being written when the PLL is on (PLLON = 1) and prevents selection of the
VCO clock as the source of the base clock (BCS = 1) if the VCO range
select bits are all clear. The VCO range select bits must be programmed
correctly. Incorrect programming can result in failure of the PLL to achieve
lock.
Register.) VRS7–VRS4 cannot be written when the PLLON bit in the PLL control
and
MUL7:MUL6:MUL5:MUL4
Table 8-3. VCO Frequency Multiplier (N) Selection
8.3.2.4 Programming the
8.3.2.5 Special Programming
0000
0001
0010
0011
1101
1110
1111
MC68HC908AZ32A Data Sheet, Rev. 2
VRS
. (See
NOTE
NOTE
for more information.) Reset initializes the bits to $6 to
8.3.2.1
VCO Frequency Multiplier (N)
PLL). A value of $0 in the multiplier select bits
Circuits,
Exceptions. A value of $0 in the VCO range
13
14
15
1
1
2
3
8.3.2.4 Programming the
8.3.3 Base Clock Selector Circuit
Freescale Semiconductor
PLL, and